# Building a pinball machine, is Arduino what I need

Hello and good day to you. My name is Josh, and my brother and I are developing plans to build a pinball machine. At this point, we are ready to begin development on the software to control the playfield devices, and have been researching what it will take to accomplish this.

We started by thinking that we would find a way to program it on a PC and interface the devices. That is what lead me to find Arduino. This device looks like it is exactly what we want, but neither of us have any real programming experience, and zero electrical engineering, so we are learning along the way. :-?

Iâ€™ve been reading alot on the site, visited the playground, and looked at some sample code. It is starting to give me an idea of how to use Arduino, but there are some questions that I have that I have not been able to find an answer for. :-/

Most devices in a pinball mahine run on 5 volts, which sounds great since USB (I believe) delivers 5 volts. But can I really use the current from the USB to run a hundred light bulbs :question

or maybe my understanding of the 5v current is inaccurate. Pinball machines have dozens of micro-switches to tell when a target was hit (or rolled over). The micro-switch, when triggered, closes a circuit; is this closed circuit the 5v inside a pinball machine? As in, does it mean that the closed circuit is delivering a 5v signal :question

However, other devices like the solenoids that drive the flippers, run at 50 volts. Can Arduino somehow signal a relay, so that it closes and delivers 50 volts? If so, how does that happen (can you explain how the hardware would be wired). Just to be clear I only know how a relay works because of car electrical, Iâ€™ve never built any electronic devices.

Also how do I power 50 volt solenoids from a 110 power outlet? I suspect I need some kind of power transformer, is that right?

What I want to first accomplish, a proof of concept if you will, is to close a microswitch (hit a target) and have a solenoid fire because of that action. If I can get that much done, then we are very much on our way. Is someone able to describe to me how that might be done from the information I have provided so far?

Please, if you have any advice or questions for me, please post or ask. My brother and I are determined to build this pinball machine, and are willing to learn all the skill necessary to complete it. I know it it will be many, but in the end it will be worth it. Thanks.

You've got a long road ahead :-) With no programming or electrical experience, you're going to have to do a lot of learning on the way.

1. There's no way USB current will be enough to power your lights, solenoids, etc. You will need power from your wall outlet.

2. When microswitches are triggered, they tell a microcontroller that something happened. These microswitches are passive -- they do not "have voltage" or current, they simply do or do not allow current to flow.

3. An Arduino board can certainly signal a relay to open and close in order to control a 50V (or other voltage) solenoid. A solenoid can also be turned on and off with a transistor (fewer moving parts). Some wiring examples of how a microcontroller board can turn high-current devices on and off can be found here.

4. You are right that you will need some kind of power transformer to get 50V DC (or whatever voltage...solenoids come in all kinds) from 110VAC. I suggest buying a ready-made switching power converter, like this.

5. Having a microswitch close then firing a solenoid will be easy once you figure out the electrical part. Focus on that first! Look at some of the example sketches available and get some basic electronics knowledge.

You might want to try and talk to this guy (JucaBlues): http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1225239439/73#73

Andrew

You might want to start by getting an old pinball machine, and then one sensor, or one control surface at a time, try reading them or controlling them with the Arduino for experience. If it turns out that itâ€™s too difficult, then youâ€™ve still got a pinball machine to play with.

Thank you for your replys. My brother and I already own a couple of pinball machines, and have plenty of part to begin fooling around with.

and it's not that I have no programming or electrical experience, I am a Windows sys admin and I do write scripts in Visual Basic, and Batch for windows and user administration tasks, and I can diagnose and repair pinball machines and E36 BMW's, but I should still be considered a novice (even a newbie) to electrical design.

I am going to disseminate the information given to me, look at the examples linked, and shall return to post my further inquiry's.

For now, I just want to keep the objective simple, and get a microswitch contact to fire a selenoid.

Since I need to learn how to deliver power to the selenoid, before I can do anything with it, that is what I am off to learn next.

any progress on this? I really would like to do this as well. Ben Heck did it with a basic stamp so it should be doable with the arduino right? http://benheck.com/bill-paxton-pinball-making-of